ICD-10 Code C84.A8 – Cutaneous T-cell lymphoma, unspecified, lymph nodes of multiple sites (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code C84.A8 – Cutaneous T-cell lymphoma, unspecified, lymph nodes of multiple sites
What it is
This code identifies cutaneous T-cell lymphoma, unspecified type, with involvement of lymph nodes at multiple sites. Use it when documentation confirms both the skin-based lymphoma and multi-site lymph node involvement, but does not name a more specific subtype.
Clinical signs
Clinical features vary; refer to documentation. Typical findings may include persistent skin lesions consistent with cutaneous T-cell lymphoma and enlarged lymph nodes in more than one region.
When to use this code
Use this code when the provider documents cutaneous T-cell lymphoma and specifies lymph node involvement at multiple sites. It is appropriate when the lymphoma subtype is not further defined in the record. If the note gives a more specific histology or site pattern, code that instead.
Do not use for
Do not use this code for cutaneous T-cell lymphoma without documented lymph node involvement, or when only one nodal site is involved. Check documentation if the record names a different lymphoma type or a more specific subtype.
Coding tip
Verify both the unspecified cutaneous T-cell lymphoma and the “multiple sites” lymph node detail before assigning C84.A8.